Intravenous administration of bone marrow-derived multipotent mesenchymal stromal cells enhances the recruitment of CD11b(+) myeloid cells to the lungs and facilitates B16-F10 melanoma colonization

Author(s)

Souza, Lucas E. B. ; Almeida, Danilo C. ; Yaochite, Juliana N. U. ; Covas, Dimas T. ; Fontes, Aparecida M.

• Document type: Journal article
• Source: Experimental Cell Research; v. 345, n. 2, p. 141-149, JUL 15 2016.
• Web of Science Citations: 2

Abstract

The discovery that the regenerative properties of bone marrow multipotent mesenchymal stromal cells (BM-MSCs) could collaterally favor neoplastic progression has led to a great interest in the function of these cells in tumors. However, the effect of BM-MSCs on colonization, a rate-limiting step of the metastatic cascade, is unknown. In this study, we investigated the effect of BM-MSCs on metastatic outgrowth of B16-F10 melanoma cells. In in vitro experiments, direct co-culture assays demonstrated that BM-MSCs stimulated the proliferation of B16-F10 cells in a dose-dependent manner. For in vivo experiments, luciferase-expressing B16-F10 cells were injected through tail vein and mice were subsequently treated with four systemic injections of BM-MSCs. In vivo bioluminescent imaging during 16 days demonstrated that BM-MSCs enhanced the colonization of lungs by B16-F10 cells, which correlated with a 2-fold increase in the number of metastatic foci. Flow cytometry analysis of lungs demonstrated that although mice harboring B16-F10 metastases displayed more endothelial cells, CD4 T and CD8 T lymphocytes in the lungs in comparison to metastases-free mice, BM-MSCs did not alter the number of these cells. Interestingly, BM-MSCs inoculation resulted in a 2-fold increase in the number of CD11b(+) myeloid cells in the lungs of melanoma-bearing animals, a cell population previously described to organize ``premetastatic niches{''} in experimental models. These findings indicate that BM-MSCs provide support to B16-F10 cells to overcome the constraints that limit metastatic outgrowth and that these effects might involve the interplay between BM-MSCs, CD11b(+) myeloid cells and tumor cells. (C) 2015 Elsevier Inc. All rights reserved. (AU)

• FAPESP's process: 08/08944-0 - The role of mesenchymal stem cells in cancer progression in a mouse melanoma model
• Grantee: Lucas Eduardo Botelho de Souza
• Support Opportunities: Scholarships in Brazil - Scientific Initiation